Condensation / Dampness

What is condensation?Condensation occurs when warm, moist air meets a cold surface such as a window, mirror or wall and causes water droplets to form. The risk of condensation depends upon how moist the air is and how cold the surfaces of the rooms are. How you ventilate and heat your home will affect the level of condensation.

What does condensation do?Condensation can cause unsightly mould that can damage clothing, furniture and wallpaper. This mould can dry, sending spores into the air that can cause breathing problems for some people.

How to avoid condensationThese four steps will help you reduce the condensation in your home.

Produce less moisture

Cooking: To reduce the amount of moisture, cover pots and do not leave kettles boiling.

Washing clothes: Put washing outdoors to dry if you can. If you have to dry clothes inside keep the windows open and the door shut. When using a tumble dryer make sure you vent it to the outside (unless it is the self condensing type).

Paraffin and portable gas heaters: These heaters put a lot of moisture into the air – one gallon of gas or paraffin produces about a gallon of water. It is important to keep the window open a little and the door closed when using these heaters. If you have a problem with condensation try to find other means of heating.

Due to the amount of moisture produced by these heaters and the damage condensation can cause, council tenants are not permitted to use paraffin and portable gas heaters in their homes.

Ventilation to remove moisture

Some ventilation is needed to remove moisture as it is being produced. Keep a small window or vent open when there is moisture in the room.

More ventilation is required in the kitchen and bathroom when cooking, washing up, bathing and drying clothes. This can be done by opening the windows wider. Better still, use an extractor fan (these come on automatically when the air becomes humid and are cheap to run). Close the kitchen and bathroom doors when these rooms are in use even if your kitchen or bathroom has an extractor fan. Doing this will stop the moisture reaching other rooms, especially bedrooms, which are often colder and more likely to get condensation.

Allow space for air to circulate in and around your furniture. Open doors to ventilate cupboards and wardrobes – filling them with too many things stops air circulating. Where possible, position wardrobes and furniture against internal walls.

Do not draught-proof where there is a fuel burning heater (e.g. gas fire) or cooker;

Do not draught-proof windows in the bathroom or kitchen.

Heat your home a little more

When the whole house is warmer, condensation is less likely.

During cold spells, a low heat for a long time is better than switching heaters on high for a short period. Where possible, try to heat the whole house. If you have central heating, set it to provide background warmth in all rooms, including unused rooms.